Boiler



Feb.-7, 1939. s. CURTIS 2,146,565

' BOILER Filed April 27, 1937 2 Sheets-Sheet 1 u 1 i ..i: 7 J

ATTORNEYS BOILER Filed April 27, 1957 2 Sheets-Sheet 2 INYENTOR Cu2" its ATTORNEYS Patented F eb. 7, 1939 l UNITED STATES vritratti" OFFICE 1 claim.

This invention relatesto boilers, an object of `the invention being to provide a boiler which constitutes either a steam boiler furnace or a Vfurnace for heating water inhot water systems,

andwhich includes a casing constituting a water chamber having an inlet at its lower portion and an outlet at. its upper portion with a fire-box vlocated inthe upper portion of the casing, and

having. an improved arrangement of flues, fire tubes, and baffles which compel the burnt gases tofltravel downwardly in a circuitous path where they are carried off by a ue at the lower end of the furnace, while the water is compelled to travel upwardly in a circuitous path, the direction of movement of the water being opposite to the direction of movement of the gases.

'Ihe invention embodies many novel features of construction and combinations and arrangements of parts, all of whichl will be more fully hereinafter described and pointed out in the claim.

In the accompanying drawings- Fig. 1 is a view in vertical longitudinal section illustrating my improved boiler, and

Fig. 2 is a View in vertical transverse section, the view being taken on the staggered line 2-2 of Fig. 1.

IU represents the casing of my improved boiler which constitutes a water chamber, and the front and rear or end walls II and I2 of the l casing, in the lower portions of said walls, may

have clean-out doors I3 as indicated in Fig. 1 of the drawings. Spaced from these end walls of the furnace are vertical plates I4 and I5, respectively, forming together with the end walls, smoke flues I6 and i1, respectively, the smoke flue I1 at its lower end communicating with the outlet flue I8 for carrying oi the burnt gases.

'I'he space between the plates I4 and I5 and the major portion of the upper part of the casing constitute a water chamber having an inlet I9 in the lower portion of the casing and an outlet 20 at the upper portion thereof. The flues I6 and I1 are connected by fire tubes 2| which are,

v of course, secured in the plates I4 and I5 and a superimposed -series of horizontal partitions constituting baffles 22, 23 and 24 are provided in the boiler. The partitions or baffles 23 and 24 extend across the ues I6 and I1 and extend into the water space between the smoke tubes 2|. The upper partition or baille 22 forms the upper end of ue I1 and also extends into the-water I space.

In the water space or water chamber above the upper partition or baille 22, my improved auxiliary combustion chamber 25 is located and l is surrounded by the water in the chamber. The front or forward end of this chamber25isfin open communication with the flue I6, whilethe inner or rear end of this chamber 25 is a closed end 26 which is of curved or generalsemi-cylindrical form. Y

This auxiliary combustion chamber 25 is preferably rectangular in cross section and within thisvchamber 25 my improvedprimary combustion' chamber 21 is located. This primary combustion chamber 21 is also preferably of rectangular form and rests upon the lower wall of the chamber 25 so that a space is provided at the top and both vsides of the combustion chamber which is in direct communication with the flue I6. The inlet end of the primary combustion chamber 21 is tapered or restricted in area forming an entrance member 28 which is closely connected with the front wall Il of the furnace. The upper wall of the primary combustion chamber 21 at its inner end is inclined downwardly,

as shown at 29, and the sides of this combustion chamber 21 are preferably covered with suitable refractory material 30.

-It is to be noted that the primaryrcombustion chamber 21 terminates short of the inner end of the auxiliary combustion chamber 25 so that the burnt gases pass from the inner end of the primary combustion chamber 21 into the auxiliary combustion chamber 25 and are directed upwardly and laterally by contact with the curved end 26 of chamber 25 so that they pass around the three sides of the combustion chamber 21 into the flue I6.

The reference character 3| is employed to indicate generally an apparatus for directing air, preferably under pressure, into the inlet end of the primary combustion chamber 21, and 32 represents a nozzle which may constitute an oil or gas nozzle. It is also to be understood that I may employ any fuel which is capable of use in the furnace.

33l represents a return pipe for conveying the steam and water of condensation, or only water if the apparatus be a hot water heater, to the inlet I9, and I preferably employ a radiator 34 through which the returning steam and water pass before entering the inlet pipe. This. radiator 34 is located in an air casing 35 having air inlets 36 at its lower end, and an air outlet flue 31 at its upper end communicating with the air entrance device 3| so that the returning steam and water serve to heat the air prior to its entrance into the combustion chamber.

The operation of the boiler is as follows: The flame from the burner 32 is directed into one end of the primary combustion chamber 21 and escapes through the inner end of said chamber 21 into the inner end of the auxiliary chamber 25 and is deflected around the combustion: chamber 2l into the flue I6 down which the gases pass and are balled by the baille 23 and are compelled to pass longitudinally through the upper set of tubes 2l into the upper portion of flue Il, and as this liue I'l isbafed by partition or bafile 24 the gases must then pass again longitudinally through the tubes 2| to the lower portion of flue I6, and thence again longitudinally through the lower set of tubes to the lower portion of ue I1 from which they escape through the outlet flue I8. Water entering the inlet i9 flows upwardly through the water chamber and horizontally back and forth in a circuitous path around the partitions or baffles 24, 23 and 22, and it will be noted, particularly by reference to Fig. 1, that the ow of the water is directly opposite to the ow of the burnt gases. Thus the Water and gases are coldest at the lower portion of the furnace and the temperature is increased to the upper portion Where the greatest amount of heat units is contained.

While. I have illustrated and described what I believe to be a preferred embodiment of my invention, it is obvious that various slight changes may be made with regard to the form and arrangement of parts without departing from my invention, and hence I do not limit myself to the precise details set forth but consider myself at liberty to make such changes and alterations as fairly fall Within the spirit and scope of the claim.

I claim: v

A boiler, including a casing constituting a Water chamber having a Water inlet at its lower portion, down draft iues in the lowerportion of the casing, an Vauxiliary fire box disposed in the upper portion of the casing and having a closed end and an open end communicating with the ues, said auxiliary re box xedly secured in the casing at its open end only, its closed end terminating short of the wall of the casing so that the auxiliary fire box is capable of free expansion and contraction, a primary re box located in the auxiliary fire box and discharging at its inner end into the auxiliary fire box, the primary re box being preferably smaller than the auxiliary re box and having a reduced end extending across a flue to permit the burnt gases in the primary box to pass through said flue, said primary box having its upper wall at its inner end inclined downwardly so that the burnt gases are discharged into the lower portion of the auxiliary re box and -directed over the top of the primary fire box into the ue.

SAMUEL CURTIS. 

